Mustrum_Ridcully
Legend
Alternatively, the Elves might actually be of aid - they hide around the Dragons lair and aim at him with their bows. So his best bet is to move across the ground and get these bastards where they can't all shoot at him. He knows he can easily beat a group of Elves in melee, but if they are spread around, his breath weapon is of little use and they can all focus their fire on him.The simulationist in me cries out that an intelligent, powerful foe (especially a mastermind type of enemy) would take care to minimize their weaknesses and maximize their advantages. From a purely "common sense" point of view, I can't see a reason why a flying critter with a breath weapon would limit its mobility to the rough equivalent to its foes.
The entertainer in me also realizes that your job is to fundamentally entertain your players. If you think that they'd be entertained by a ferocious melee, you've just got to figure out a reason why to make it plausible (if such things matter to you and your group). I'd suggest that you view this as an opportunity to develop story or add layers onto your plot.
Here's a few ideas. Feel free to use and abuse as you see fit.
• The forest is within the hunting grounds of a tribe of elves. They would love to see the dragon defeated, but they simply don't have the melee beaters to directly engage it--they specialize in hit-and-run tactics themselves. Their hunters have devised a harpoon designed to tear away large sections of wing from such creatures. They will gladly provide the characters with these harpoons, which can be used in the first round to tear off the dragon's wings.
• The characters can convince the local lord to re-take a border tower and fortify it, using it as a base to attack the dragon from. This is a ruse, of course. What the characters are really up to is luring the dragon inside the tower, where its flight is useless once they slam the portcullis closed.
• You can have the characters visit a shaman/druid/witch/whatever, an isolated mystic that dwells within the forest. The mystic feels threatened by the dragon, having perhaps battled it in the past or working against its machinations. Perhaps after performing a service for this mystic (another adventure!), the mystic enacts a powerful ritual to rouse the spirits of the storm and the eternal winds. When the characters battle the dragon, these spirits slam the dragon back to the ground if it tries to fly.
What he doesn't know is that the PCs are planning to intercept him.
This way, the Dragon can choose to fly - but he is attacked by a barrage of arrows every time he does. (Ruleswise, this might work like a hazard or trap - or maybe more than one, to be "dangerous enough".)
You might not be able to negate the Dragons flight entirely (he must logically reach a minimum height to be targettable by those Archers), but it keeps him close enough for lots of attacks to work.